Researchers in the United States have carried out a comparison of four of the most popular diets and the low-carbohydrate 'Atkins diet' has come up trumps.
The study, by researchers at the Stanford University School of Medicine, which is one of the largest and longest-ever conducted, found that those randomly assigned to follow the Atkins diet for a year, lost more weight than the other participants, but also experienced the most benefits in terms of cholesterol and blood pressure.
Lead researcher Christopher Gardner, PhD, assistant professor of medicine at the Stanford Prevention Research Center, says very-low-carbohydrate diets for weight loss have attracted skepticism and been dismissed by many health professionals, but the diet is a viable alternative.
For the study 311 pre-menopausal, non-diabetic, overweight women were randomly assigned to follow either the Atkins, Zone, LEARN or Ornish diet which were chosen because they represent the full spectrum of low- to high-carbohydrate diets.
The popular Atkins diet represents the lowest carbohydrate diet, the Zone diet is also low-carbohydrate, focusing on a 40:30:30 ratio of carbohydrates to protein to fat, a balance said to minimize fat storage and hunger.
The LEARN (Lifestyle, Exercise, Attitudes, Relationships and Nutrition) diet follows national guidelines reflected in the U.S. Department of Agriculture’s food pyramid - low in fat and high in carbohydrates, while the Ornish diet, based on bestseller Eat More, Weigh Less by Dean Ornish, is very high in carbohydrates and extremely low in fat.
The women in all four groups attended weekly diet classes for the first eight weeks of the study and each received a book outlining the specific diet to which they were assigned.
Over the remaining 10 months of the study, the women's weight and metabolism were regularly checked, and what they were eating was monitored by random phone calls.
Gardner says one of the strengths of the $2 million study was that it reflected real-world conditions, as the women had to prepare or buy all their own meals, and not everyone followed the diets exactly as prescribed in the books.
By the end of the twelve month period the 77 women assigned to the Atkins group had lost an average of 10.4 pounds; those assigned to LEARN lost 5.7 pounds; the Ornish group lost 4.8 pounds and women on the Zone lost 3.5 pounds, on average.
Some participants in all four groups lost up to 30 pounds.
It was also found that the women following the Atkins diet had larger decreases in body mass index (BMI), triglycerides and blood pressure; their high-density lipoprotein, the good kind of cholesterol, increased more than the women on the other diets.
Gardner suggests the Atkins diet had the overall best results because of it's very simple message, "get rid of all refined carbohydrates to lose weight" which is in line with a major concern over the American diet and the increasing consumption of refined sugars.
Gardner also says the Atkins diet is the best at encouraging people to drink more water, and when people replace sweetened beverages with water, they don't generally eat more food; they simply consume fewer calories over the course of the day.